---
title: Reading agent state
icon: "lucide/ArrowLeft"
description: Read the realtime agent state in your native application.
---
import { ImageZoom } from "fumadocs-ui/components/image-zoom";
import RunAndConnect from "@/snippets/integrations/pydantic-ai/run-and-connect.mdx"
import { IframeSwitcher } from "@/components/content"

<IframeSwitcher
  id="shared-state-read-example"
  exampleUrl="https://feature-viewer.copilotkit.ai/pydantic-ai/feature/shared_state?sidebar=false&chatDefaultOpen=false"
  codeUrl="https://feature-viewer.copilotkit.ai/pydantic-ai/feature/shared_state?view=code&sidebar=false&codeLayout=tabs"
  exampleLabel="Demo"
  codeLabel="Code"
  height="700px"
/>

<Callout type="info">
  This example demonstrates reading from shared state in the [CopilotKit Feature Viewer](https://feature-viewer.copilotkit.ai/pydantic-ai/feature/shared_state).
</Callout>

## What is this?

You can easily use the realtime agent state not only in the chat UI, but also in the native application UX.

## When should I use this?

You can use this when you want to provide the user with feedback about your agent's state. As your agent's
state updates, you can reflect these updates natively in your application.

## Implementation

<Steps>
  <Step>
    ### Run and connect your agent
    <RunAndConnect components={props.components} />
  </Step>
  <Step>
    ### Define the Agent State

    Create your Pydantic AI agent with a stateful structure. Here's a complete example that tracks language:

    ```python title="agent.py"
    from textwrap import dedent

    from pydantic import BaseModel
    from pydantic_ai import Agent, RunContext
    from pydantic_ai.ag_ui import StateDeps


    class AgentState(BaseModel):
        """State for the agent."""
        language: str = "english"


    agent = Agent("openai:gpt-4o-mini", deps_type=StateDeps[AgentState])


    @agent.instructions()
    async def language_instructions(ctx: RunContext[StateDeps[AgentState]]) -> str:
        """Instructions for the language tracking agent.

        Args:
            ctx: The run context containing language state information.

        Returns:
            Instructions string for the language tracking agent.
        """
        return dedent(
            f"""
            You are a helpful assistant for tracking the language.

            IMPORTANT:
            - ALWAYS use the lower case for the language
            - ALWAYS response in the current language: {ctx.deps.state.language}
            """
        )


    app = agent.to_ag_ui(deps=StateDeps(AgentState()))

    if __name__ == "__main__":
        import uvicorn
        uvicorn.run(app, host="0.0.0.0", port=8000)
    ```

  </Step>
  <Step>
    ### Use the `useCoAgent` Hook
    With your agent connected and running all that is left is to call the [useCoAgent](/reference/hooks/useCoAgent) hook, pass the agent's name, and
    optionally provide an initial state.

    ```tsx title="ui/app/page.tsx"
    import { useCoAgent } from "@copilotkit/react-core"; // [!code highlight]

    // Define the agent state type, should match the actual state of your agent
    type AgentState = {
      language: "english" | "spanish";
    }

    function YourMainContent() {
      // [!code highlight:4]
      const { state } = useCoAgent<AgentState>({
        name: "my_agent", // MUST match the agent name in CopilotRuntime
        initialState: { language: "english" }  // optionally provide an initial state
      });

      // ...

      return (
        // style excluded for brevity
        <div>
          <h1>Your main content</h1>
          {/* [!code highlight:1] */}
          <p>Language: {state.language}</p>
        </div>
      );
    }
    ```

    <Callout type="warn" title="Important">
      The `name` parameter must exactly match the agent name you defined in your CopilotRuntime configuration (e.g., `my_agent` from the quickstart).
    </Callout>

    <Callout type="info">
      The `state` in `useCoAgent` is reactive and will automatically update when the agent's state changes.
    </Callout>

  </Step>
  <Step>
    ### Give it a try!
    As the agent state updates, your `state` variable will automatically update with it! In this case, you'll see the
    language set to "english" as that's the initial state we set.
  </Step>
</Steps>

## Rendering agent state in the chat

You can also render the agent's state in the chat UI. This is useful for informing the user about the agent's state in a
more in-context way. To do this, you can use the [useCoAgentStateRender](/reference/hooks/useCoAgentStateRender) hook.

```tsx title="ui/app/page.tsx"
import { useCoAgentStateRender } from "@copilotkit/react-core"; // [!code highlight]

// Define the agent state type, should match the actual state of your agent
type AgentState = {
  language: "english" | "spanish";
};

function YourMainContent() {
  // ...
  // [!code highlight:7]
  useCoAgentStateRender({
    name: "my_agent", // MUST match the agent name in CopilotRuntime
    render: ({ state }) => {
      if (!state.language) return null;
      return <div>Language: {state.language}</div>;
    },
  });
  // ...
}
```

<Callout type="warn" title="Important">
  The `name` parameter must exactly match the agent name you defined in your CopilotRuntime configuration (e.g., `my_agent` from the quickstart).
</Callout>

<Callout type="info">
  The `state` in `useCoAgentStateRender` is reactive and will automatically
  update when the agent's state changes.
</Callout>

## Intermediately Stream and Render Agent State

By default, the Pydantic AI Agent state will only update _between_ Pydantic AI Agent node transitions --
which means state updates will be discontinuous and delayed.
